二连盆地形成的地球动力学背景

GEODYNAMIC BACKGROUND ON FORMATION OF ERLIAN BASIN

肖安成 杨树锋 陈汉林

Xiao Ancheng Yang Shufeng Chen Hanlin

内蒙东部盆地群是发育在海西褶皱基底上的中新生代断陷盆地.目前的盆地面貌是多期次构造叠加的结果.盆地的构造演化经历了早-中侏罗世和早白垩世伸展断陷盆地期、晚侏罗世末和早白垩世晚期构造反转期及晚白垩世以来的整体抬升期5个不同阶段.早-中侏罗世断陷盆地的形成与东亚板块的差异运动和深部作用有关;晚侏罗世末期的构造反转与蒙古-鄂霍茨克洋闭合和大洋板块的俯冲相联系;早白垩世的断陷盆地源于太平洋构造域俯冲过程中所产生的弧后深部作用;早白垩世末期的盆地反转可能是中国东部左旋走滑带作用的结果;而晚白垩世以来则属于区域性的稳定调整过程.

The basin group in the east part of Nei Monggol are Middle Cenozoic fault-depressed basins developed on Hercynian basement. The landform of the basins is the result of multiple superimposition of structures. The basin's structural evolution underwent five different evolution stages such as stretch-depressed stage in Early-Middle Jurassic and Early Cretaceous Periods, the reversion stage in late Early Jurassic and late Early Cretaceous and the complete uplift stage since Late Cretaceous. The formation of the Early-Mildle Jurassic fault-depressed basin was related to the differential movement of the East Asian Plate; the reversion of the structures was the result of the close of Monggol-Okhotsk Ocean and the structures of oceanic plate, the Early Cretaceous fault-depressed basin was derived from back-arc deep-seated action caused by the subduction of the Pacific tectonic tract; the late Early Cretaccous basin reversion might beresulted from sinistral strike-slip of East China.

10.11743/ogg20010211